Turkey says it will send troops into northern Iraq, in the event of an American attack on Iraq, to insure that Kurds did not try to set up an independent Kurd state. Turkey has also said it would intervene if the Iraqi Kurds tried to occupy the city of Kirkuk (just south of the Kurdish zone in northern Iraq that American and British aircraft protect). Kirkuk, and its oil fields,  has traditionally been Kurdish, but over the last 20 years, Saddam has been moving Arabs into Kirkuk, and Kurds (forcibly) out. Neither Turkey, nor Saddam, want the Kurds to get oil.